Modern packet-switched networks accommodate a greater number of users and a larger amount of traffic than ever before. Many users have sought to harness the increased bandwidth and connectivity to other users to exchange large files, such as multimedia content and software. To this end, users often engage in so-called Peer-to-Peer (P2P) transfers, in which data is exchanged directly between users, rather than between the user and a central server. Such an approach is advantageous, as it allows sharing of massive amounts of information without the need for a central server with the requisite storage and bandwidth.
Unfortunately, P2P transfers can have a significant impact on the Quality of Experience of other users in the network. As an example, a typical BitTorrent transfer may establish hundreds or even thousands of connections to other peers in the network. Establishing this many connections uses up available bandwidth in transmission lines and burdens the network equipment used to route the packets to the appropriate destination. As the number of users of P2P software has increased, the negative effects on service provider networks have multiplied.
Service providers have been forced to address these problems caused by P2P transfers. Given the significant expenses associated with adding additional equipment, service providers are reluctant to address the P2P problem by simply increasing the capacity of the network. Furthermore, increasing capacity may not be a solution at all, as P2P transfers have the potential to overwhelm any amount of available bandwidth.
As a result, service providers have started to regulate transmission of P2P traffic over their networks. Service providers initially treated all P2P traffic as suspect and gave other transfers preferential treatment over P2P traffic. Such an approach has resulted in significant legal problems for service providers. For example, in the United States, the Federal Communications Commission (FCC) has held that Internet Service Providers (ISPs) must not discriminate against all P2P traffic, as it violates users' rights to select applications and content of their choice. “Net-neutrality” advocates, those who support fair and equal access to the Internet, have mounted similar legal challenges.
Legal problems aside, treating all P2P traffic as suspect operates on a number of false assumptions. First, such an approach assumes that all P2P transfers are illegitimate, when, in actuality, many content owners use P2P as a cheap, efficient way of allowing users to obtain their content. As an example, many freeware or shareware software developers distribute their software using P2P transfers. Second, the initial approach taken by service providers assumes that P2P transfers have no technical benefits. In fact, P2P transfers allow a massive amount of information to be shared without the need for a large infrastructure of content servers.
Thus, it would be desirable to implement a solution that allows service providers to regulate illegal or otherwise illegitimate P2P transfers, while allowing legitimate P2P transfers to continue as usual. Such a solution would allow service providers to minimize the use of bandwidth for illegal P2P transfers, while preserving net neutrality and harnessing the benefits of P2P for legal transfers.
Unfortunately, many P2P software designers and users of such software are aware of efforts by ISPs to regulate P2P transfers and include measures to circumvent such efforts. In particular, many P2P software programs implement encryption, such that the contents of the packets transmitted from a source peer to a destination peer are only discoverable using a decryption key known to the destination peer. In implementations in which a network element inspects the contents of the packets, taking an action based on the encrypted contents of the packets becomes difficult, if not impossible.
Thus, it would be further desirable to implement a solution that allows ISPs to selectively regulate illegal or otherwise illegitimate P2P transfers, even when the data transmissions between clients are encrypted. In particular, there is a need for a solution that regulates P2P transfers based on the unencrypted information exchanged in order to establish a connection.
For the foregoing reasons and for further reasons that will be apparent to those of skill in the art upon reading and understanding this specification, there is a need for management of encrypted P2P transfers based on the underlying content.